Threaded sink strainer housing

ABSTRACT

A housing for securing a sink strainer body portion of a sink drain assembly in a sink drain opening is disclosed. The housing clamps an annular lip defining the sink drain opening between a flange on the sink strainer body portion and a flange on the housing. The housing has a circular thin-walled threaded portion which threadably engages a threaded spout on the sink strainer body portion so as to be positively advanced on rotation thereof to secure the sink strainer body portion in the sink drain opening. The housing expedites installation of sink drain assemblies, reduces manufacturing costs and self-centres the sink strainer body portion upon securing same in the sink drain opening.

[451 May 6,1975

[ THREADED SINK STRAINER HOUSING [75] Inventor: William T. Richards,Toronto,

Ontario, Canada [73] Assignee: Premier Tool and Die Limited,

Toronto, Ontario, Canada [22] Filed: Oct. 12, 1973 [21] Appl. No.:406,037

[52] US. Cl. i 4/286; 4/288; 285/206 Dutcher 285/206 Deeke 4/288 PrimaryExaminerl-lenry K. Artis Assistant Examiner-James E. Bryant, Ill

[57] ABSTRACT A housing for securing a sink strainer body portion of asink drain assembly in a sink drain opening is disclosed. The housingclamps an annular lip defining the sink drain opening between a flangeon the sink strainer body portion and a flange on the housing. Thehousing has a circular thin-walled threaded portion which threadablyengages a threaded spout on the sink strainer body portion so as to bepositively advanced on rotation thereof to secure the sink strainer bodyportion in the sink drain opening. The housing expedites installation ofsink drain assemblies, reduces manufacturing costs and self-centres thesink strainer body portion upon securing same in the sink drain opening.

9 Claims, 3 Drawing Figures I PATENTEDHAY' 61975 SHEET 1 [1F 2 FIG(PRIORART) PATENTEDMAY' ems SHEET 2 BF 2 THREADED SINK STRAINER HOUSINGFIELD OF THE INVENTION This invention relates to sink drain assembliesand in particular, improvements in a housing used to secure a sink drainassembly in a sink drain opening.

BACKGROUND OF THE INVENTION Sink drain assemblies principally used intodays sinks particularly in kitchen sinks, comprise a sink strainerbody portion which is mounted through a sink drain opening and issecured therein by placing a housing with a flange over the body portionwhich projects beyond the underside of the sink wall. The sink wall isclamped between a flange on the sink strainer body and the housingflange by threading a nut onto the threaded spout portion carried by thesink strainer body. An annular rubber gasket may be placed between thehousing flange and the underside of the sink wall. A tailpiece may bethreaded onto the threaded spout portion so that a drain pipe can beconnected to the sink drain.

During assembly of this type of sink strainer arrangement, the housingis free to move about as the nut is threaded onto the threaded spout sothat as the housing flange is brought to bear on the underside of thesink wall, difficulties are encountered in centering the sink strainerbody in the sink drain opening. To further add to this problem adifficult manipulation is required in positioning the rubber gasket,housing and nut under the sink during assembly of the unit whileattempting to maintain the sink strainer body within the sink drainopening. Such an assembly method may be further complicated by workingin very poor lighting so that a clear view of the installation ishindered.

Most existing kitchen sinks have an annular lip which is inclinedoutwardly relative to the sink wall thereby making the clamping actionof the sink wall between the flange of the housing and the flange of thesink strainer body insecure, because the flange of the housing issubstantially horizontal as compared to the inclined lip, so that therubber gasket is poorly clamped between the respective flanges.

The sink drain assembly according to this invention overcomes theabove-noted problems by providing a housing having an integrally thinwalled threaded portion provided thereon which may be adapted to threadonto the threaded spout of the sink strainer body portion such as thoseof the prior art. The threaded portion of the housing may extend from areduced end thereof and, at the other end of the housing, a flange maybe formed or an annular rim where the inside diameter of the rim isgreater than the diameter of the sink drain opening. The sink strainerbody portion may be easily secured in the sink drain opening bythreading the housing onto the threaded spout to positively advance thehousing flange or annular rim towards the underside of the sink wall toclamp same between the respective flanges. A rubber gasket need not berequired in this installation because the housing flange may be formedso that it rotatably slides over the annular inclined lip which definesthe sink drain opening, to positively clamp the sink wall between therespective flanges. The housing flange is therefore inclined upwardly ata slope which corresponds with the downward slope of the annular lip sothat the outer surface of the lip mates with the inner surface of thehousing flange. Self-centering of the sink strainer body is cffected byusing such a housing flange arrangement because as the flange rotatablyslides over the annular lip, the contacting surfaces of the flange andannular lip interact so that the longitudinal axis of the housingbecomes coincident with the axis of the sink drain opening therebydrawing the sink strainer body portion to the centre of the sink drain.

By using a housing according to this invention, the sink strainer bodymay be centered in the sink drain opening and secured therein by asimple one-step operation of threading the housing onto the threadedspout of the sink strainer body, without requiring the arranging andmanipulating of an individual rubber gasket, housing and nut, therebymaking installations in poor lighting situations and difficult-to-get-atdrains much easier and more convenient.

A housing design according to this invention may be manufactured atcomparatively reduced production costs because two pieces of materialare eliminated in the assembly, namely, the rubber gasket and a threadednut. The transportation costs of such a unit are also lowered becausefrom a packaging aspect, the weight of the entire unit is substantiallyreduced.

SUMMARY OF THE INVENTION It is therefore an object of the invention toprovide a sink drain assembly which may be simply and more convenientlyinstalled.

It is a further object of the invention to provide a housing forsecuring a sink strainer body portion in a sink drain opening whichcentres the sink strainer body in the sink drain opening duringinstallation.

It is another object of the invention to provide a sink drain assemblywhich may be manufactured at a lower cost and transported more easilythan existing comparable prior art assemblies.

It is yet another object of the invention to provide a housing'having aflange so formed to rotatably slide over an inclined annular lip whichdefines the sink drain opening to centre the sink strainer body in thedrain opening during assembly.

A BRIEF DESCRIPTION OF THE DRAWINGS These and other objects, advantagesand features of the invention are discussed in more detail hereinafterin association with the accompanying drawings in which:

FIG. 1 is a cross-sectional view of a sink having a sink drain assemblymounted therein which is characteristic of prior art devices;

FIG. 2 is an exploded view of a sink strainer body mounted through asink drain opening and of a housing according to this invention;

FIG. 3 is a cross-sectional view of a sink having a sink drin assemblyaccording to this invention mounted therein.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sink drain assemblycommon to those of the prior art is shown in FIG. 1 as mounted in a sinkdrain opening in the sink wall 12 which is defined by an outwardlyinclined annular lip 14. A tubular sink strainer body portion 16 ismounted through the sink drain opening and flange 18 formed at one endof the tubular sink strainer body retains same inthe opening. To securethe sink strainer body 16 in the sink drain opening, a

housing 20 is slid over the portion of the sink strainer body whichprojects beyond the sink wall 12 with a rubber gasket 22 placed betweena flange 24 of the housing and the underside of the sink wall 12. Thesink strainer body 16 has a threaded spout 26 extending from the lowerend thereof. Over the threaded spout, a nut 28 is threaded to positivelyadvance the housing 20 towards the underside of the sink wall 12,thereby clamping the sink wall between the flange 18 and the rubbergasket 22.

As shown in the structure of FIG. 1, the outwardly inclined annular lip14 is common to most sink drain openings so that with the prior artdevices, selfcentering of the sink strainer body 16 as the housing 20 isbrought to bear on the underside of the sink wall 12 is not effected noris there a good clamping action between the flange 18 and the annulargasket 22 because of the difference in the inclination of flange 24 andthe annular lip 14 of the sink wall 12. As a result, the task ofcentering the sink strainer body 16 in the sink drain opening isinefficient due to the required manual alignment of the housing with theannular gasket 22 as the nut 28 is being threaded onto spout 26 whileattempting to maintain the sink strainer body 16 in the centre of thesink drain opening.

The sink drain assembly according to this invention, is shown in FIG. 2where a sink strainer body 30 which may be identical to the sinkstrainer body 16 of the prior art, is mounted through a sink drainopening defined by an annular lip 32 of sink wall 34. The sink strainerbody 30 has a flange 36 which rests on the upper side of the annular lip32 to retain the sink strainer body 30 in the sink drain opening. Forpurposes of resisting leakage of water between the flange 36 and theupper side of the annular lip 32, a suitable waterproofing putty may besandwiched between the opposing surfaces. The housing 38 which is usedto secure the sink strainer body 30 in the sink drain opening is adaptedto fit over the sink strainer body 30 and has a flange 40 at the upperend thereof. A circular thinwalled threaded portion 42 is formed at thelower end thereof, which is integral with the housing 38, and is adaptedto be threaded onto threaded spout 44 of the sink strainer body 30. Ahexagon nut-shaped gripping surface 46 may be provided at the restrictedor neck portion of the housing 38 adjacent the threaded portion 42 sothat when the unit is assembled a secure clamping of the sink wall 34between flanges 36 and 40 is ensured.

FIG. 3 illustrates the sink drain assembly according to this inventionas assembled where a suitable waterproofing putty 37 is sandwichedbetween flange 36 and the upper side of the annular lip 32. The housing38 is threaded onto spout 44 to clamp the annular lip 32 between flange36 and flange 40 so that the sink strainer body 30 is secured in thesink drain opening. As implied, the housing 38 encloses the lowerportion of the sink strainer body 30 which projects exteriorly of thesink wall 34.

The flange 40 of the housing 38 has an upwardly inclined upper surfaceadapted to mate with the downwardly inclined lower surface of annularlip 32, both surfaces having the same relative slope. As the housing 38is threaded onto the spout 44, the inner surface of flange 40 rotatablyslides over the outer surface of the annular lip 32. The shape of theouter surface of the annular lip 32 may be considered as being that of atruncated cone so that as flange 40 of the housing 38 contacts theannular lip, the rotational movement of the housing causes thelongitudinal axis of the housing to become coincident with the centralaxis of the sink drain opening, therefore centering the sink strainerbody 30 as it is drawn into the sink drain opening. A self-centering ofthe sink strainer body during assembly of the unit is thereforeeffected.

To ensure that the sink strainer body 30 is securely mounted in the sinkdrain opening, a hexagon nut formation 46 is provided at the neckportion of the housing 38 to permit wrench tightening of the housing.However, it is understood that other alternative gripping surfaces maybe provided on the housing 38, and for that matter, in someapplications, the housing 38 may be gripped by hand and tightenedsufficiently to secure the sink strainer body 30.

Although the use of a flange 40 has been illustrated as being outwardlyinclined, an alternative arrangement of the upper end of the housing 38may be used where the upper end presents an annular rim having an insidediameter greater than the diameter of the sink drain opening so that therim contacts the underside of the annular lip 32 and due to theinclination of the lip 32, the self-centering action is realized becausethe inner surface of the rim rotatably slides over the outer surface ofthe lip.

In assembling the sink drain assembly according to this invention, thesink strainer body portion 30 is mounted through the sink drain openingand a suitable waterproofing putty is sandwiched between the flange 36and the upper surface of the annular lip 32. The sink strainer body isthen secured by simply holding it in the opening and threading thehousing 38 onto the threaded spout 44 to positively advance the housingflange 40 towards the underside of the annular lip 32. Either by hand orusing an appropriately sized wrench the housing can be brought to bearfirmly against the lip 32 to clamp same between the flanges 36 and 40.As discussed hereinabove, this clamping action automaticallyself-centres the sink strainer body 30 in the sink drain opening. It isunderstood that the housing may be used in applications where a matingof the annular lip and the housing flange is not a good fit becausesufficient clamping action may still be achieved however, theself-centering feature could be sacrificed.

The sink drain assembly as shown in FIG. 3 may be fabricated fromacceptable plumbing materials such as various stainless steel alloys andcorrosion resistant counterparts. However, it is understood that variousother material substitutes may be used, such as rigid plastics.

The thin-walled threaded portion 42 of housing 38 may be fabricated byrolling the thread onto the tubular portion. Similarly, the thread onthe spout 44 may also be rolled according to accepted machiningpractices. In comparing this type of fastening arrangement for the sinkstrainer body 30, as compared to that used in the prior art whichrequires a threaded nut 28 usually formed of zinc, the cost of thehousing including the threaded portion is substantially less than thatrequired to fabricate the housing 20 and nut 28 of the prior art.Therefore not only a more convenient and simpler method of installing asink strainer body is realized, but also a substantial reduction inproduction cost results. Also, the weight of the entire unit is reducedthereby cutting down on packaging and transportation costs of the sinkdrain assembly unit. The amount of material required in forming ahousing 38 is also much less than that required in forming the housingand separate zinc nut as used in the prior art.

While various embodiments of the invention have been illustrated anddescribed, it will be understood that variations therein may be made aswill be apparent to those skilled in the art without departing from thespirit of the invention or scope of the appended claims.

The embodiments of the invention in which an exclusive property orprivilege is claimed are defined as follows:

1. In a sink drain assembly, a housing, a tubular sink strainer body,for mounting through a sink drain opening in a sink, and having anannular flange at one end thereof which is adapted to contact the innersurface of a sink wall surrounding said opening and a threaded spoutextending from the outer end of said sink strainer body, said housingbeing substantially tubular and of an interior dimension to permitpositioning of said housing over the portion of said sink strainer bodywhich projects exteriorly of said sink wall for securing said sinkstrainer body in said sink drain opening; the improvement comprising acircular thin-walled threaded portion provided at an end of saidhousing, said circular threaded portion being integral with saidhousing, the axis of said circular threaded portion being coincidentwith the longitudinal axis of said tubular portion, the threads on saidcircular thin-walled threaded portion being rolled threads and sodimensioned as to threadably engage said threaded spout to enable saidhousing to be positively advanced on rotation thereof to clamp said sinkwall between said flange and the other end of said housing; said otherend of said housing presenting an integral annular body portion havingan inside diameter greater than the diameter of said sink drain open- 2.In a sink drain assembly of claim 1, said annular body portion being aflange.

3. In a sink drain assembly of claim 1, said housing having an exteriorcircumferential surface with at least one flat surface on the peripherythereof to permit gripping of said housing with a wrench.

4. In a sink drain assembly of claim 2, said sink drain opening beingdefined by an annular lip inclined away from the interior of said sinkwall; said flange on said housing being inclined at a slope whichcorresponds with the slipe of the inclined annular lip, said flangeadvancing over said inclined annular lip as said flange is brought tobear on said lip as said housing is positively advanced due to rotationthereof to urge the longitudinal axis of said sink strainer body towardsthe longitudinal axis of said sink drain opening.

5. In a sink drain assembly of claim 3, said housing having a neckportion from which said threaded portion extends, said at least one flatsurface being formed about said neck portion.

6. In a sink drain assembly of claim 3, said'exterior circumferentialsurface comprising a series of intersecting substantially planarsurfaces which define a hexagonal body portion.

7. A sink drain assembly housing which is used to secure a sink strainerbody in a sink drain opening, comprising a tubular body portion, acircular thin-walled threaded portion at an end of said housing, anannular body portion positioned at the other end of said housing; saidcircular threaded portion and annular body portion being integral withsaid tubular body portion the axis of said circular threaded portionbeing coincident with the longitudinal axis of said tubular bodyportion, the threads on said circular thin-walled threaded portion beingrolled threads, and the inside diameter of said annular body portionbeing greater than the diameter of said sink drain opening.

8. A sink drain assembly housing of claim 7 wherein said annular bodyportion is a flange inclined relative to the circumferential wall ofsaid tubular body portion.

9. A sink drain assembly of claim 8 wherein said tubular body portionhas an exterior circumferential surface comprising a series ofintersecting substantially planar surface which define a hexagonal bodyportion.

1. In a sink drain assembly, a housing, a tubular sink strainer body,for mounting through a sink drain opening in a sink, and having anannular flange at one end thereof which is adapted to contact the innersurface of a sink wall surrounding said opening and a threaded spoutextending from the outer end of said sink strainer body, said housingbeing substantially tubular and of an interior dimension to permitpositioning of said housing over the portion of said sink strainer bodywhich projects exteriorly of said sink wall for securing said sinkstrainer body in said sink drain opening; the improvement comprising acircular thin-walled threaded portion Provided at an end of saidhousing, said circular threaded portion being integral with saidhousing, the axis of said circular threaded portion being coincidentwith the longitudinal axis of said tubular portion, the threads on saidcircular thin-walled threaded portion being rolled threads and sodimensioned as to threadably engage said threaded spout to enable saidhousing to be positively advanced on rotation thereof to clamp said sinkwall between said flange and the other end of said housing; said otherend of said housing presenting an integral annular body portion havingan inside diameter greater than the diameter of said sink drain opening.2. In a sink drain assembly of claim 1, said annular body portion beinga flange.
 3. In a sink drain assembly of claim 1, said housing having anexterior circumferential surface with at least one flat surface on theperiphery thereof to permit gripping of said housing with a wrench. 4.In a sink drain assembly of claim 2, said sink drain opening beingdefined by an annular lip inclined away from the interior of said sinkwall; said flange on said housing being inclined at a slope whichcorresponds with the slipe of the inclined annular lip, said flangeadvancing over said inclined annular lip as said flange is brought tobear on said lip as said housing is positively advanced due to rotationthereof to urge the longitudinal axis of said sink strainer body towardsthe longitudinal axis of said sink drain opening.
 5. In a sink drainassembly of claim 3, said housing having a neck portion from which saidthreaded portion extends, said at least one flat surface being formedabout said neck portion.
 6. In a sink drain assembly of claim 3, saidexterior circumferential surface comprising a series of intersectingsubstantially planar surfaces which define a hexagonal body portion. 7.A sink drain assembly housing which is used to secure a sink strainerbody in a sink drain opening, comprisng a tubular body portion, acircular thin-walled threaded portion at an end of said housing, anannular body portion positioned at the other end of said housing; saidcircular threaded portion and annular body portion being integral withsaid tubular body portion the axis of said circular threaded portionbeing coincident with the longitudinal axis of said tubular bodyportion, the threads on said circular thin-walled threaded portion beingrolled threads, and the inside diameter of said annular body portionbeing greater than the diameter of said sink drain opening.
 8. A sinkdrain assembly housing of claim 7 wherein said annular body portion is aflange inclined relative to the circumferential wall of said tubularbody portion.
 9. A sink drain assembly of claim 8 wherein said tubularbody portion has an exterior circumferential surface comprising a seriesof intersecting substantially planar surface which define a hexagonalbody portion.